FIGURE 2:

Native Blt1p forms homotetramers. (A) SDS–PAGE of purified recombinant Blt1p-hexahistidine stained with Coomassie blue with standards in the left lane. (B) Elution of purified Blt1p in 20 mM Tris, pH 8.0, 20 mM NaCl, 0.5 mM EDTA, and 1 mM DTT from a calibrated Superdex 200 gel filtration column followed by ultraviolet absorption. (C) Distributions of sedimentation coefficients determined by sedimentation velocity analytical ultracentrifugation at 20°C, assuming a continuous c(S) distribution. Conditions are the same as B. Three concentrations of Blt1p: dashed, 0.1 μM; gray, 1.0 μM; and black, 10 μM.